
class Engine{
    public void start(){}
    public void rev(){}
    public void stop(){}
}

class Wheel{
    public void inflate(int psi){}
}

class Window {
    public void rollup(){}
    public void rolldown(){}
}

class Door{
    public Window window = new Window();
    public void open(){}
    public void close(){}
}

public class Car {
    public Engine engine = new Engine();
    public Wheel[] wheel = new Wheel[4];
    public Door
        left = new Door(),
        right = new Door();
    public Car(){
        for (int i  = 0; i < 4;i++)
            wheel[i] = new Wheel();
    }
    public static void main(String[] args) {
        Car car = new Car();
        car.left.window.rollup();
        car.wheel[0].inflate(72);
    }
}
